#include <stdio.h>
#include <stdlib.h>
#include <time.h>

int main()
{
    time_t start, end;
    start = time(NULL);
    printf("start = %ld\n",start);
    for(int i=0; i<123456789; i++);
    end = time(NULL);
    printf("end = %ld\n",end);
    printf("time = %ld\n",end-start);
    return 0;
}
